Electroluminescent Panel Life
 

(The higher the voltage and frequency, the brighter the lamp will glow and the shorter its useful life.)

Answering the question of the life of FLATLITE, for any electroluminescent based product,
is a somewhat long answer.

EL does not fail to light so it technically has NO end of life, rather it is the decaying luminance level (brightness) in a particular application that determines when it is no longer useful.

The decaying luminance is exponential - meaning more rapidly early and extremely slow later in time, which is also greatly affected by how the phosphors are powered (this means the inverters output wave shape, voltage and frequency) and by the ambient temperature the lamps are being run in (cold temperatures yield better results than warmer temperatures).

All EL technologies share the same characteristics with the major variation being the
quality of the base phosphor material with the secondary factor being the way the lamp is manufactured.

The phosphors available from each manufacturer are graded according to their specific life and brightness characteristics. If the same exact grade is being used by two manufacturers, their methods of making or driving the lamp may produce results that differ as much as 25%. This is why the decision to use EL technology for an application should be independent of what a particular supplier may quote for "life".

Comparing two EL technologies must be done with all the factors (power, temperature, phosphor grade) equal, which may not be possible given the data normally available from the different manufacturers.

Our Flatlite inverters employ an active compensation scheme, so more voltage is fed to the lamp as it ages early in its life. This compensation scheme, combined with variable starting brightness levels, greatly varies the useful life of a product. In one test, for example, samples were run at 25, 50, 75 and 100% starting voltage. After 2 years of running 24/7, the lamp started at the 25% level was the brightest of the 4 samples and the other 3 were virtually the same.

In Signage applications where the brightness required is high but the “on time” (duty cycle) is only the night time hours as in a bus or taxi sign, the Useful life is approximately 12 –18 months.

In Aisle Lighting applications like Movie Theaters, both the brightness is low and the duty cycle is low resulting in a Useful life of 5 years or more.

In outdoor Architectural Lighting applications, the required brightness is relatively low but the duty cycle is about 50%. The Useful Life of this type application can be 3 – 5 years. EL lamps do not “burnout”, in time they will become dim enough to require replacement.